She knows me since my parents got her. I never lived with them, though. Sometimes she's playful and loving and other times she's angry and trying not to let me into the house.
I think the type/breed of the dog is important info missing here. The age also might be helpful to know. But regardless, time is needed to adjust to a new situation. Don't push any interactions and give as much space as needed. After enough time (which will vary greatly from dog to dog) the dog will become more comfortable with your new prescence.
She's an akita/husky mix. 3 years old. I arrived a week ago and she was lovely and accepted me. Today, when my parents were gone, she was kind of angry and sad to be left at home with us. She didn't wanna be with me so I let her. When i fed her later this morning that's when she came closer. I fed her, turned around and cleaned the kitchen. After she was finished eating she got very "angry" (don't know the right term) and snarled at me. I almost couldn't walk past her (which I had to to get to my desk). She looked and sounded like she was ready to fight me.
So, that breed/mix is a tricky one. She could be showing agression either to establish dominance or more likely out of territorial protection. Especially if she does not exhibit this behavior when your parents are home.
So I think there are a few avenues available to you, none of which are a quick fix.
Time. It will simply just take time for her to accept you and recognize that you are not a threat to "her family" and her territory
Association. Try to replace the association she has when she sees you. Rather than exhibiting something fearful or territorial, bring her a snack everytime she first sees you. You might be able, over time, to have her associate you with "yummy treat" instead of "intruder"
Body Language. Watch for her body language. Dogs will usually give you fair warning before they commit to aggression. If you start recognizing these patterns it becomes easier to avoid.
Bonding. When you parents are home and the dog isn't acting agressive, try to participate in a bonding activity. Go for walk, maybe be the one to start feeding and giving water so they look at you as a care provider, if there is an activity she likes (like fetch, or being brushed) participate in this activity WITH your parents present.
Regulate Emotions. Easier said than done, but try not to exhibit fear. The dog will sense it and react to it. If you are fearful and can not control your emotions, just remove yourself from the situation until you regain composure
Establish Dominance. This can and should be started in the prescence of your parents. Give commands and reward a positive response.Right now, when it is just the two of you alone, she is the one in charge. Reverse that and she'll feel no need to be aggressive towards you.